The present invention relates to a light distribution system, and components of the system for maintaining beam integrity and continuity, wherein a plurality of beams are each directed from the system by illumination directors, each remote from a source and disposed in a system configuration, and more particularly to a system in which system configuration, i.e. a set of spatial positions of illumination directors, may be changed while maintaining beam integrity and continuity.
As used on the present context, a radial light distribution system comprises a geometric, multidirectional collimator for surrounding a quasi point source. Collimation means surround the quasi point source for providing radial light beams. The radial beams pass through respective conveyance means to directing means. The conveyance means may comprise tubes or walls surrounding a beam, a defined open space or solid transmissive means. The directing means directs light away from the system to a space to be illuminated. Each directing means is remote from the collimation optics and source. The directing means are, in effect, non-wired light sources for room illumination. The beams thus directed leave the system through exit means. For purposes of the present description, the term "illumination director" refers to means which direct light beams away from the light distribution system to achieve illumination of, for example, a point, space or volume. An illumination director may comprise a directing means and its corresponding exit means.
A particularly successful and efficient example is illustrated in my U.S. Pat. No. 5,130,908 entitled Architectural Member Comprising Illumination System. My Provisional Application 60/005,621 filed Oct. 19, 1995 also provides for a multiple beam projection lighting system. The patent and the provisional application are commonly owned with the present application, and their disclosures are incorporated herein by reference.
Concepts and examples of radial collimation of light, from a quasi point source and distribution of light are presented in my commonly owned patent application Ser. No. 08/201,466 filed Feb. 25, 1994 entitled Architectural Lighting Distributed from Contained Radial Light, the disclosure of which is incorporated herein by reference. A quasi point source is provided and radiation from the source is divided in to separate radial paths. Conveyance means, which may comprise either solid, hollow or empty paths, carry light to remote directing means and through exit means to direct light away from the system in order to illuminate selected areas. In this manner, a system with many exit means and one source can replace prior art systems needing many sources. Expense in terms of wiring, source maintenance and energy consumption is greatly reduced by a distribution system.
Further, my commonly owned, copending patent application Ser. No. 08/610,303, the disclosure of which is also incorporated herein by reference, discloses a method and apparatus of controlling beam divergence in a system that provides a fixed lighting configuration.
While this embodiment has been successful for light distribution in which distributing means are fixed in an architectural member, it is highly desirable to provide a system in which the length of conveyance means may be changed and in which providing a directing means with the capacity to direct beams in any of a plurality of selectable positions. This enables one distribution system to be used to illuminate one set of objects or spaces in a room configured for one sort of display. When illumination requirements are reconfigured, the light distribution means can also be reconfigured. Reconfiguration is achieved by changing the spatial relationship of each illumination director with respect to the source and the collimation optics.
Successful reconfiguration, i.e. reconfiguration in which light loss between the source and the exit means is substantially eliminated, can not be provided simply by lengthening various components or simply revolving them about an axis fixed with respect to the source. Such arbitrary adjustments do not take in to account maintaining the integrity of a directed radial beam. Maintaining integrity includes maintaining the shape of the directed radial beam, i.e. its cross section. It is necessary to maintain continuity of the beam, e.g. as by minimizing beam divergence due or distortion to mechanical adjustment of a system in adjusting from one configuration to a next configuration. Increasing divergence can cause additional bounces off walls in conveyance means. Commonly, light is lost on each bounce. It is desirable to minimize light loss. Other mechanical adjustment, e.g. angular displacement of directing means from a first position, may affect the light transmission in other ways. Consequently, opportunities for light loss abound.
An adjustable system provides opportunities to formulate lighting standards to meet particular illumination requirements in a given room or other space. In the present description, lighting standard refers to a standard way of using a light system of a particular type to suit a standard requirement. For example, one particular type of lighting system is track lighting. One standard requirement is illumination of a vertical wall. The lighting standard in this system comprises placing a track parallel to the wall at a distance of two feet and providing a plurality of spot lights on the track.
Additionally it is desirable construct a system of the type described in a manner in which light from two or more sources may be combined. One source may be sunlight, further enhancing energy efficiency of the present invention.